Apparatus for analyzing gaseous mixtures



May 15, 1934. A KENNEDY 1,959,242

APPARATUS FOR ANALYZING GASEOUS MIXTURES Filed Oct. 11, 1928 Inventor A114. [Kennedy 17 W W Attorneys Patented May 15, 1934 PATENT OFFICE APPARATUS FOR ANALYZING GASEOUS MIXTURES Absalom M. Kennedy, Tuscaloosa, Ala., assignor,

by mesne assignments, to Moto-Vita Corporation, a corporation of Application October 11,

'7 Claims.

This invention relates to apparatusfor analyzing gaseous mixtures and moreparticularly to apparatus for determining the proportion of combustible constituents present.

Somesubstances in the presence of combustible fluid mixtures have the property of promoting combustion along theirsurfaces, thereby causing the combustible constituents to unite with air or oxygen which may be present. Anexample of such a substance is platinum which is a catalyst of combustion under certain temperature conditions. Thus, if the exhaust gas from an internal combustion engine or-flue gas from a boiler stack is confined with air or oxygen in the presence of a catalyst of combustion, the temperature of the latter will increase by an amount depending upon the proportion of the combustible constituents present. By utilizing this phenomenon in a combustion analyzer, an indication may be obtained of the percentage of combustibles present in exhaust fuels. This will enable the operator of the engine or boiler withflwhich the device is associated to regulate the fuel to air ratio so that substantially ideal combustion conditions will result. This of course will result in an enormous saving of fuel. However, in products of combustion resulting from the operation of internal combustion engines, boilers and the like; foreign substances are apt to be present such as carbon particles, moisture or lead oxide-if ethylgasoline is used, which will be deposited'upon the catalyst of combustion so as to produce deleterious effects and prevent the functioning thereof at its utmost efficiency.

An object of this invention, therefore, is to indicate the presence of a combustible gas or gases in a gaseous mixture.

Another object of the invention is to indicate the proportion of combustible constituents present in a gaseous mixture.

Still another object of the invention is to mechanically separate foreign substances from the gases to be analyzed while at the same time using the motion of the gases to aspirate a sumcient amount of a substance capable of combining chemically therewith to complete combustion.

A feature of this invention, therefore, resides in creating a vertical flow of the gases tobe analyzed, whereby the heavy foreign substances which may be present are expelled.

Another feature of the invention providesfor aspirating an element capable of chemically combining with the combustible constituents of the gases to be analyzed within the vortical flow.

Still another feature of the invention resides Delaware 1928, Serial No. 311,924

in positioning an elementcapable of promoting a chemical reaction between thecombustible constituents of the gases to be analyzed within the vortical flow, but out of the path of the heavier foreign substances which may be present.

Still another feature of the invention resides in utilizingchanges in pressure of a volatile fluid resulting'from changes in temperatureto indicate the proportion of combustible content in a gaseous mixture.

Another featureresides in utilizing a temperature indication to determinethe proportion of combustibles present in a gaseous mixture.

Other objects of the invention, will, in part, be obvious and will, in part, appear hereinafter.

The invention accordingly: comprises the features of construction, combinations of elements, and arrangement of parts, which will be exemplifled in the construction hereinafter set forth and the scope of the application of which will be indicated in the'claims.

' A better understanding of the invention may be had by reading the following description together with the accompanying drawing wherein:

Fig. 1 is a sectional elevation of one embodiment of the invention taken along line 11 of Fig. 2, and

Fig. 2 is a sectional view taken along line 2--2 of Fig. 1.

Referring to the drawing, a pipe 10 is shown which may be the exhaust pipe ofan internal combustion engine or a boiler flue through which gases are presumed to be traveling in the direction indicated by the arrows. Located within the pipe 10' and facing upsteam with respect to the flow-of gases, is a tube 11 similar to a Pitot tube. Communicating with the tube 11 is a conduit 12 which is connected to a cylindrical casing 13 having a tangential opening 14 therein communicating with the conduit 12. The casing 13 is provided with a tangential outlet opening 16, to'which is connected an exhaust outlet conduit 17 so thatthe gases entering and. leaving the casing 13 produce a vertical whirl which serves to impel the heavy foreign matter which may be present in the exhaust gases against the walls of the cylinder 13, thus separating them from the gaseous mixture to be analyzed.

It will be apparent that the apparatus just described is designed to produce a relatively high velocity flow of gases through the casing 13 for the-purpose set forth and that such velocity flow ispredicated upon the high velocity. flow through the conduit 10: It is to be-understood', however, that the means illustrated and described for mm 110 ducing such a velocity flow may be modified in many ways known to the art and that the invention is not necessarily limited to the specific means disclosed.

Centrally disposed with respect to the casing 13 is an aspirating opening 18 in communication with the atmosphere through which air may be drawn by the above mentioned gas vortex to the interior of the casing for admixture with the gaseous products of combustion. It will be noted that the outlet opening 16 is considerably larger than the inlet opening 14. As the velocity of the gases throughout the vortex is substantially the same, a larger volume of gases will leave the casing 13 than will enter through the inlet 14. The difference in volume of course will be made up by the air aspirated through the aperture 18. This larger outlet opening thus precludes any possibility of an excess pressure being built up in the casing as to expel exhaust gases through the air inlet opening 18.

Disposed within the casing 13 intermediate the outer wall thereof and the opening 18 so as to be away from the path of foreign matter carried within the gases, are two hollow bodies or bulbs 21 and 22 which may be made of any suitable material and which contain fluid preferably of a volatile nature. Connected to the hollow bodies 21 and 22 are tubes 23 and 24 which communicate with a manometer 26 for indicating the pressure differential between the two bodies. One of the hollow bodies such as 21 is surrounded by a catalytic agent such as by a winding of platinum wire 27 whereby a reaction between the oxygen of the air and the combustible content of the exhaust gas is effected along the surface of the catalyst of combustion 27. This surface combustion will raise the temperature of the body 21 over that of the hollow body 22 and this increase in temperature will be proportional to the proportion of combustible constituents in the exhaust gases. This increase in temperature will expand the fluid resulting in an increase in the pressure within the hollow body 21 which will be greater than the pressure exerted by the fluid within the hollow body 22. This pressure difference may be indicated by the manometer 26 which has a fluid therein movable in response to the difference in pressure in the tubes connected therewith. This indication reveals the proportion of the uncombined combustible products in the exhaust gases.

From the foregoing description, the operation of the device is apparent. Exhaust gases flowing through the conduit 10 are entrained by the tube 11, flow through the tube 12 and enter the cylindrical casing 13 tangentially thereof and at a velocity which is sufiiciently high to create a vortical whirl therein. As the gases are expelled from the cylindrical casing tangentially thereof, the solid particles and other foreign matter which may be present in the gases are carried along the surface of the casing and expelled through the outlet. The vortical whirl of the gases aspirate air through the aperture 18 which will combine chemically with the combustibles in the gases along the surface of the catalytic agent 21. The increased temperature resulting raises the fluid pressure within the tube 21 over that in the tube 22, the extent of which is determined by the difference in the level of the fluid in the manometer 26. The indicating portion of the manometer may be positioned on an instrument board or upon a dashboard, if used with an automobile, so that the operator will be apprised of the proportion of combustibles present in the exhaust gases so that he may adjust the fuel-to-air ratio of the power plant to produce substantially ideal combustion conditions.

Since certain changes may be made in the above construction and different embodiments of the invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the accompanying drawing shall be interpreted as illustrative and not in a linnting sense.

It is also to be understood that the following claims are intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

What I claim is:

1. A device for testing gaseous mixtures comprising a cylindrical casing having a tangential inlet opening for admitting gases thereto, a tangential outlet opening and a central inlet opening adapted to admit air within said casing, means for effecting a reaction between the combustible content of the gases and the oxygen content of the air, and means responsive in accordance with the extent of said reaction.

2. In a device of the character described, a cylindrical casing having a tangential gas inlet opening, a tangential gas outlet opening and a central inlet opening for admittng air within said cylindrical casing, means within the casing and disposed intermediate the air inlet opening and the outer wall of the casing for effecting a reaction between the combustible content of the gases and the oxygen content of the air, and means responsive in accordance with the extent of said reaction.

3. In apparatus for testing the exhaust gases of an internal combustion engine, the combination with the exhaust conduit of the engine, of means for entraining gases from the exhaust conduit, a cylindrical casing having a tangential inlet opening connected to the entraining means, a central aspirating opening communicating with the atmosphere and a tangential outlet opening for the gases and entrained air, a pair of hollow bodies each containing an expansible fluid and positioned intermediate the aspirating opening and the inlet and outlet opening of the casing,

a catalytic agent in association with one of the hollow bodies, and means for measuring the pressure differential between the fluids in the two hollow bodies.

4. In apparatus for testing the exhaust gases of an internal combustion engine, the combination with the exhaust conduit of the engine, of means for entraining gases from the exhaust conduit, a cylindrical casing having a tangential inlet opening connected to the entraining means,

a central aspirating opening communicating with the atmosphere and a tangential outlet opening for the gases and entrained air, a pair of hollow bodies each containing an expansible fluid and 14. positioned intermediate the aspirating opening and the inlet and outlet openings of the casing,

a catalytic agent in association with one of the hollow bodies, and a manometer connected to both hollow bodies for indicating the pressure 1 differential between the fluids in the two bodies.

5. A device for indicating the presence of combustibles in a gaseous mixture comprising a vortex chamber, an aperture in the center of said vortex chamber for the admission of air, means associated with said chamber responsive to temperature variations and having a catalytic agent associated therewith, other temperature responsive means associated with said chamber, said catalytic agent acting to promote surface combustion on the temperature responsive means with which it is associated when combustible containers, said catalytically active element acting to promote surface combustion on the container with which it is associated and means operated by the pressure of said volatile fluid for indicating the temperatures of said containers.

7. Apparatus for testing gases, comprising a source of gases under pressure, an analyzing chamber having tangential inlet and outlet openings, means utilizing the pressure of said source for conducting gases to said chamber and producing a vortical whirl therein, an aperture in said chamber through which air is drawn by said gaseous flow for mixture therewith, and a catalytic agent exposed to said flow adapted to promote the chemical combination of constituents in said gas with air.

ABSALOM M. KENNEDY.

CERTIFICATE OF CORRECTION.

Patent No. 1,959,242. May 15, 1934,

ABSALOM M. KENNEDY it is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, line 48, for "vertical" read vortical; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 19th day of June, A. D. 1934.

Bryan M. Battey (Seal) Acting Commissioner of Patents; 

